The present invention relates to sighting apparatus for archery bows, and more particularly, to a peep sight mechanism and peep sight turner associated with a bow string used by an archer on a fully drawn bow string to compensate for the adverse effects on optimum peep sight alignment caused by the rotation or twisting of the bowstring as it is drawn.
An archer, in operating a bow, mounts a nock of an arrow at a nocking point on a bowstring of the bow prior to drawing the bowstring. A shaft of the arrow is mounted on an arrow rest positioned generally at a midpoint on one side of the bow. The archer then draws the bowstring back generally using the fingers of one hand while holding the bow with the opposite hand. Traditionally, to establish proper arrow trajectory once the bowstring is fully drawn, the archer typically placed the hand gripping the bowstring at a reference point on or near the archer's face and also aligns his or her eye directly behind a vertical plane defined by a plane passing through the side of the bow against which the arrow is rested and the drawn bowstring for target sighting.
Such a target sighting process was prone to error. To improve the accuracy and precision of the sighting process, bows and bowstrings were provided with various sighting devices to assist the archer in establishing proper arrow trajectory.
Such sighting devices have included sighting pins for installation on the bow and peep sights for installation in or on the bow string. Sighting pins are adjustably mounted on and extend horizontally from the bow at a preset position above the arrow rest and are used in conjunction with a peep sight mounted in spaced relation above the nocking point so as to be in the line of sight of the archer. Thus, use of peep sights and sighting pins improved the archers ability to establish proper arrow alignment and trajectory.
In practice, however, traditional peep sights have been difficult to use. The bowstring in or on which the peep sight is mounted tends to twist or rotate across the archer's fingers as the bowstring is drawn rearwardly. Such a bowstring rotation, no matter how slight, will tend to misalign the opening of a conventional peep sight in relation to optimum alignment of the peep sight. Often the bowstring rotation is sufficient to completely prevent the use of the peep sight for sighting the target. Further, because both of the archer's hands and arms are in use in holding the bow in the fully drawn and cocked position, the archer's hands are generally not free to adjust the alignment of the peep sight.
Various devices are taught by the prior art to overcome such a problem. The Topel U.S. Pat. No. 4,116,194 discloses a peep sight mounted in a bowstring and connected by an elastic cord to a bow. As the bowstring is drawn, the elastic cord stretches and exerts force upon the peep sight to maintain the peep sight in proper alignment for viewing of the target. Such an elastic cord presents particular problems when used with a compound bow having a lattice of bowstrings through which the elastic cord must be threaded. As such, the elastic cord tends to become tangled or bound in the lattice of compound bowstrings when the bowstring is released. Further, when used with a compound bow, the elastic cord impinges on the bowstrings when the bowstring is released and increases a noise level which is desirable to maintain at a very low level while hunting. Even when used with a conventional recurve bow, the elastic cord tends to unevenly distribute the forces normally imposed on the arrow at the knocking point by the bowstring in the drawn position, causing unpredictable effects on trajectory.
The Miller U.S. Pat. No. 4,454,857 discloses an apparatus which also attempts to overcome the problem in peep sight misalignment caused by the rotation of the bowstring during drawing of the bow. The Miller patent discloses a peep sight having the form of a disc with an elongated hollow hub tightly receiving the bowstrings and connected by spokes to the outer rim of the peep sight. However, because the peep sight openings for sighting the target are the openings between the spokes of the apparatus, when the bowstring is fully drawn, the archer must tilt his head in order to view the target past both the string and the elongated hollow hub which tightly receives the bowstring. Thus, the archer's line of sight is offset and is angular with respect to the axis of the arrow. Such a peep sight apparatus, therefore, creates a source of error for which the archer must compensate in addition to other factors such as distance, elevation, and wind.
The Fletcher U.S. Pat. No. 4,011,853 discloses a peep sight apparatus having the general shape of a disc with a centrally positioned frusto-conical shaped peep sight opening. The apparatus disclosed in the Fletcher patent may be used for sighting targets when it is up to 50 degrees out of optimum alignment. When the Fletcher apparatus is greater than 50 degrees out of alignment, the target can no longer be viewed through the apparatus by aligning the target with the sighting pins. Further, because the small opening positioned at the bottom of the semiconical depression is relatively small, the effective opening for sighting the target is reduced in proportion to the misalignment of the peep sight and the target blurs well before reaching a misalignment of 50 degrees.
Accordingly, it is highly desirable to provide a peep sight apparatus providing a plurality of openings which may generally be used to sight a target, even after the peep sight has rotated with the bowstring in excess of 50 degrees during the drawing of the bow string. It is also highly desirable to provide a peep sight apparatus which can be conveniently adjusted by the archer while the archer holds the bowstring fully drawn prior to release of the arrow.